Search Engine www.edaboard.com

White Led Transistor

Add Question

7 Threads found on edaboard.com: White Led Transistor
If white led used then it requires 3 cells. Check led with 50 ohm resistor sepeately if it glows with battery and solar panel.
How to make a simple switch to turn off a led during daylight using only one transistor, jfet or mosfet, and a light dependent resistor ? No other components, besides the white led and a 3.5V cell ? Is there a way to turn on at dusk, off at dawn with that minimum of components ? Or, does a reverse coheficient LDR exists, (...)
You wont get much of a flash from your circuit, the current through the leds is going to be quite low, probably in the region of 15mA. If you want a bright flash, use white leds as suggested and a driver transistor, preferably a power MOSFET to discharge the capacitor into them. If you have 3 x 24 leds at (...)
bushygs I suspect you have destroyed the BC557. You need some current limiting, i.e. a resistor, in series with your led to protect both the transistor and the led. A red led will have a forward voltage of around 2V when forward biased, and a blue or white one will have around a 4V drop. Add in the CE (...)
Hi, Of course it's not a typical application of the 555 BUT it should work except that KJ6EAD is right you're going to blow your led. The best way to NOT blow your led is to insert a resistor (270 Ω for a white led on 12v) between the led anode and the transistor emitter to limit (...)
is it possible to run light sensing circuit on proteus 7.1.i am using white led as light source and L14G2 as photo transistor.please help me.thanks in advance.
Hi the white led can not handle 125 ma current and it will burn rapidly reduce the current to about 15 ma if the led diameter 5mm and if it is 3mm reduce the current to about 3-5 ma that will be safe.I have aquestion does that transistor can hanle 125 ma current?. Also you didn t tell what happens when you switch the (...)